Fix conversion of valid_range metadata to tuple in viirs_edr reader

[djhoese]

While testing viirs_edr with our upcoming release of Polar2Grid 3.1, @kathys noticed that the AWIPS tiled writer fails to handle valid_range metadata that is a numpy array. It assumes it is a tuple or something else boolean-able. I can't find any documentation in the Satpy documentation on this, but I'm fairly certain that we tend to recommend either removing metadata fields like valid_range or to convert them to tuples. This PR converts the viirs_edr reader's metadata to a tuple for valid_range and now writing to AWIPS tiled files works as expected.

• Closes #xxxx
• Tests added
• Fully documented

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 95.94%. Comparing base (8bcd427) to head (aff4f31).
Report is 7 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2833   +/-   ##
=======================================
  Coverage   95.94%   95.94%           
=======================================
  Files         366      366           
  Lines       53504    53522   +18     
=======================================
+ Hits        51332    51350   +18     
  Misses       2172     2172           

Flag	Coverage Δ
behaviourtests	4.04% <0.00%> (-0.01%)	⬇️
unittests	96.03% <100.00%> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[coveralls]

Pull Request Test Coverage Report for Build 9586294239

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 30 of 30 (100.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.001%) to 96.041%

---

Totals
Change from base Build 9520945640:	0.001%
Covered Lines:	51579
Relevant Lines:	53705

---

💛 - Coveralls

[djhoese]

I need this pull request for my work. Since everyone is going on vacation, I'm going to flex my github permission muscles and push this through. The overall fix is pretty simple, but we should probably have a larger discussion about the "standard practice" being utilized here.